Adaptive Fast Charging Control Technique for Current Mode DC-DC Buck Converters

Autor: Chang-Che Hsieh, 謝昌哲
Rok vydání: 2014
Druh dokumentu: 學位論文 ; thesis
Popis: 103
The switching regulators have been widely used in power supply systems and are becoming a common building block in modern VLSI systems, especially for the growing number of battery-operated portable devices. With the evolution of the process, the supply voltage and the signal level decrease. Therefore, fast load transient response to keep output voltage stable and clean becomes very critical for voltage regulators nowadays. The output current slew rate of the switching converter is restricted by the inductor in conventional architecture. In this thesis, we propose adaptive fast charging control technique for current mode dc-dc buck converters to improve this issue. In this architecture, we add adaptive fast charging control technique, which has some new paths connected to the output capacitance and the control loop. When the output load current becomes large or small instantly, the additional current path will source or sink current to the output and compensate the control loop to achieve fast transient response. This technique is implemented with TSMC 0.25μm CMOS process. Measurement results show that the recovery time is within 6~7μs. Compared with the conventional design, which typically gives 12μs, the recovery time is reduced by about 40-50%. In addition, since the adaptive fast charging control only works in transient response, the power conversion efficiency is still in a range of 78%~85% with load current between 100 mA and 500 mA in the proposed architecture.
Databáze: Networked Digital Library of Theses & Dissertations